Snow is freshwater. It forms from the freezing of water vapor in the atmosphere, which is naturally devoid of significant salt content. While seawater can freeze to form sea ice, the process of freezing actually expels most of the salt, leaving behind relatively fresh ice.
Understanding the Difference
- Freshwater: Water with minimal dissolved salts. Examples include rain, snow, and most rivers and lakes.
- Saltwater: Water with a high concentration of dissolved salts, predominantly sodium chloride. Ocean water is the primary example.
Several sources confirm that snow, the primary component of land ice, is freshwater:
- The National Snow and Ice Data Center (https://nsidc.org/learn/parts-cryosphere/sea-ice/science-sea-ice) explains that while seawater freezes, the salt is largely excluded from the forming ice crystals, resulting in relatively freshwater ice.
- The U.S. Geological Survey (https://www.usgs.gov/special-topics/water-science-school/science/ice-snow-and-glaciers-and-water-cycle) indicates that glaciers and ice sheets (which are largely accumulated snow) are part of the freshwater cycle.
- A Reddit discussion (https://www.reddit.com/r/antarctica/comments/1akoz6j/why_is_the_ice_and_snow_in_antarctica_mosrly/) specifically addresses the freshwater nature of Antarctic snow and ice. Even sea ice, when formed, is largely freshwater due to salt rejection during freezing.
- Multiple other sources (https://wtamu.edu/~cbaird/sq/2013/08/14/how-do-icebergs-lose-their-salt/, https://www.amnh.org/content/download/154153/2561707/file/grace-passage-1-student-version.pdf) emphasize that icebergs, originating from land ice (and therefore snow accumulation), are freshwater.
